Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations cover readOnly/openWorld, and the description adds substantive behavior: one request per call, no page content returned, redirect chain capped at 10 hops, http followed to https, and per-header pass/warn/fail verdicts. These are cost and output-shape facts an agent cannot derive from the annotations alone.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core verb and scope, then the mode breakdown, then the sibling caveat. Dense but every clause carries information; the semicolon-delimited mode list is efficient though slightly hard to scan.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the full burden of describing return values and does so per check mode, including hop limits and artifact scope. Nothing needed to call it correctly appears missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 50% because the 'check' enum has no description; the prose compensates fully by defining what each enum value returns (status code/final URL/timing/headers, hop-by-hop chain, security-header audit with pass/warn/fail). It also restates and clarifies the https-only URL constraint.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Live HTTP check of ANY public https URL') and enumerates exactly what each of the three check modes returns. It explicitly distinguishes itself from get_site_health, a close sibling, so an agent can select between them without opening schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives one explicit alternative and the condition selecting it: for an account site's homepage, get_site_health already has this data from the daily audit. It also implies scope by restricting to public https URLs, but provides no general when-not guidance or exclusions for the other listed checks.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.